Global Patent Index - EP 0586975 B1

EP 0586975 B1 19960410 - Method for the isolation of 2-naphthylamine-1,5,7,-trisulphonic acid

Title (en)

Method for the isolation of 2-naphthylamine-1,5,7,-trisulphonic acid

Title (de)

Verfahren zur Isolierung von 2-Naphthylamin-1,5,7,-trisulfonsäure

Title (fr)

Procédé d'isolement de l'acide 2-naphtylamine-1,5,7,-trisulfonique

Publication

EP 0586975 B1 19960410 (DE)

Application

EP 93113653 A 19930826

Priority

DE 4229997 A 19920908

Abstract (en)

[origin: EP0586975A1] 2-Naphthylamine-1,5,7-trisulphonic acid can be precipitated in an advantageous manner under exactly defined conditions. To this end, reaction mixtures are employed which contain 15-40% by weight of trisulphonic acid and 60-85% by weight of H2SO4 or oleum. These mixtures are diluted to 20-80% by weight of H2SO4 based on the total amount of H2SO4 and H2O, the temperature being kept at 30-80 DEG C and the ratio of added H2SO4 to originally present H2SO4, calculated as 100% strength H2SO4, being at least 0.1. During the dilution step, the H2SO4 content is never short of the above 20% limit by more than 10%.

IPC 1-7

C07C 303/44; C07C 303/06; C07C 309/47

IPC 8 full level

C07C 303/06 (2006.01); C07C 303/44 (2006.01); C07C 309/47 (2006.01)

CPC (source: EP KR)

C07C 303/06 (2013.01 - KR); C07C 303/44 (2013.01 - EP KR); C07C 309/47 (2013.01 - KR)

Designated contracting state (EPC)

CH DE GB IT LI

DOCDB simple family (publication)

DE 4229997 A1 19940310; CN 1089940 A 19940727; DE 59302165 D1 19960515; EP 0586975 A1 19940316; EP 0586975 B1 19960410; JP H06192214 A 19940712; KR 940006999 A 19940426

DOCDB simple family (application)

DE 4229997 A 19920908; CN 93117217 A 19930908; DE 59302165 T 19930826; EP 93113653 A 19930826; JP 24355693 A 19930906; KR 930017977 A 19930908